/**
 * Copyright 2017 Confluent Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 **/

package io.confluent.ksql.parser.tree;

/**
 * When walking Expressions, don't traverse into SubqueryExpressions
 */
public abstract class DefaultExpressionTraversalVisitor<R, C>
    extends DefaultTraversalVisitor<R, C> {

  @Override
  protected R visitSubqueryExpression(SubqueryExpression node, C context) {
    // Don't traverse into Subqueries within an Expression
    return null;
  }
}
